In Dandy Gilver and A Spot of Toil and Trouble there are two stately homes. One – Castle Bewer – is a dark, damp Gothic pile where a production of Macbeth is being mounted. Thus the Bewer family hope to keep the wolf from the door. Castle Bewer is more or less Caerlaverock Castle in Dumfriesshire.

The other house is Mespring. And nothing like it exists in Dumfriesshire, that’s for sure. It’s fictional. It truly is fictional. But I know some of its over-the-top décor is identical to the décor of real stately homes I’ve wandered round, with my mouth hanging open, unable to believe that people ever chose such insane levels of ornamentation for walls, floor and furniture. Visits to Chatsworth have definitely helped me write this. Hopetoun too. And Drumlanrig Castle, where I first saw leather wallpaper of the kind described here.

I thought it would be fun to have the Annandales of Mespring be quite sanguine about the look of their house, even while they prepare to open it to the public at a shilling a pop. Here’s some of the best fun I’ve ever had writing fiction – Billy Annandale giving Dandy Gilver an advance peek at the splendours of Mespring:

It was, quite simply, staggering. A game of rugby football could have taken place in this hall and still left room for the household to have tea undisturbed by the fire. It was enormous, like a cathedral, and stuffed to its waistline with marble in every conceivable shade. The floor was mustard with green veins, the fireplace ginger with pink, and the pillars were the nasty brown of chocolate ice-cream. The statues were good plain white but they were dwarfed by what was above them. Surely, I thought, this hallway had been raised at some time in its long life. Surely no architect had planned all of this at once. For on top of the green, brown and pink marble excesses was another room entirely, as though its floor had fallen through and they had simply left it hovering there. The upper room was a riot of painted frescos, crawling over walls and ceiling. Literally crawling in most instances, I noted, since the tableaux – as such tableaux tend to – suggested that people do not walk around or sit down but that instead they drape themselves on couches if mortal or clouds if not, so that a crowd of them painted on a grand scale is simply a tangle of arms and legs and the odd bit of floating drapery. Gods, cherubs, graces, nymphs and puttis rolled about from the top of the hideous marble on one wall all the way across to the top of the hideous marble on the other, eyes beseeching, limbs waving and clothes mostly falling off.

‘It’s-’ I said.

Billy Annandale guffawed. ‘It certainly is. Let’s keep walking. I’m afraid there’s a lot more of it before we get to the long gallery.’ He cleared his throat modestly, an impeccable imitation of a very correct footman, or perhaps a clerk in a rather staid bank. ‘This, as you see, is the great hall and if we ascend the great stairs’ – he waved to both sides, pointing out the disputed Rembrandt on the way – ‘we arrive at the great drawing room.’ Here, in a chamber forty feet long if it was an inch, as well as marble and tapestries and a fresco of the birth of Venus with a great many more flailing arms and legs and even less clothing, there was also a quantity of veneered wood in that very intricate parquetry that I am afraid makes me think of dartboards. Add the fact that the carpet was Victorian and so had not yet begun to fade the way that older carpets do – so kind to their surroundings – and the fact that the curtains were set about with tassels and tucks and looked like the costumes of a battalion of pantomime dames, and the drawing room was worse than the hall.

‘And now the great dining room,’ Billy said, flinging open one of a pair of doors.

‘What on earth is that?’ I asked, stepping through into an even longer room, which seemed to have been afflicted with some kind of fungus.

‘It’s leather wallpaper,’ Billy said. ‘Stamped, silvered and gilded. Do you like it?”

‘Uh,’ I said. ‘It’s ingenious.’

Again Billy only laughed and said: ‘if you’re wondering how much better it would look with more gilding covering the leather . . . Behold the great music room.”

‘Oof,’ I said, for here the gilt was dazzling and the marble border above it – quite ten feet deep – had even more naked nymphs, all managing to play violins, pipes and lutes while rolling on their backs.

‘We did think of redoing the chairs,’ said Billy, waving at the rows of those uncomfortable little gilt and velvet affairs one sits on during music recitals. They are wonderful at keeping one awake even after a solid dinner, but most unfortunately in this case they had been covered in what I can only call orange. It was not the gold of the leather walls nor even the cream of the damask curtains. It was an unrepentant orange. ‘But really,’ Billy went on, ‘what’s the use? If we actually started to look at any of it with the eye of taste we would curl up in little balls and weep wouldn’t we? Anyway, finally the ordeal is over and we have arrived at . . . the great gallery.’

We passed through another tall door and it was a testament to the garish nature of the rooms behind us that this – a sixty-foot gallery with red walls, red carpet and gargantuan portraits in those gold encrusted frames that look as though they have been overrun by barnacles – seemed almost soothing.

‘God knows what the trippers will make of it all,’ Billy said.

‘I think,’ I told him, quite honestly, ‘they will be over-awed and delighted but, because not everything is exactly in accordance with modern tastes, they won’t be quite so covetous and dissatisfied with their own little villas and flats as they might be otherwise.’

Billy stared at me. ‘What a nice woman you are,’ he said. ‘They’ll be happy to have paid their shilling to see this ugly barn of a place and they’ll go home to cream paint and plain rugs quite content?’